Known in the prior art are fitness tools designed to allow a user to perform a fitness exercise.
Some of these tools comprise a resistant weight and a mobile element connected to the weight which allow the performance of a plurality of fitness exercises for training a plurality of human body muscles. Other tools define constraints allowing the user to train by performing predetermined movements and using the body as the resistant load.
For example, European patent EP1402925 to the same Applicant as this invention, describes an exercise machine comprising a frame, a plurality of pulleys fixed to the frame, a cable trained around the pulleys, a pair of resistant loads to which the respective ends of the cable are connected, and a mobile element in the form of a handgrip slidably associated with the cable and designed to be gripped by the user and to be moved along a path for performing a fitness exercise.
Patent document EP1506798 in the name of the same Applicant as this invention describes an exercise machine which can be used by a plurality of users at the same time.
The exercise machine comprises a plurality of exercise zones, each designed to be occupied by a user performing an exercise. In each exercise zone, there is a cable connected to a resistant load which allows the user to perform the fitness exercise.
The exercise machines described above are very versatile and allow the user to perform a plurality of different exercises for training a plurality of body muscles.
Whatever the exercise, it is essential that the user perform the exercise correctly so as to gain the most benefit from it.
In effect, performing an exercise incorrectly, besides reducing the benefits associated with that exercise (the benefit being, for example, improving muscle power and developing muscle tone), involves a risk of muscle damage and, in the long term, may lead to serious degenerative diseases of the spinal column.
Fitness establishments such as gyms normally employ trainers, that is to say, physical education specialists, responsible for supervising fitness equipment users during exercise sessions.
If a trainer believes that a user is not performing an exercise properly, he or she provides the user with instructions and explanations on how the exercise should be performed.
For economic reasons, a gym has a relatively small number of trainers compared to the number of fitness equipment users. Thus, each trainer is obliged to keep an eye on different fitness equipment users in turn, which means that the attention dedicated to supervising the exercises of any one particular user is inevitably limited.
Moreover, when not inside a gym, a user of fitness equipment very often performs exercises without any supervision.
For example, a person using a fitness tool at home usually performs an exercise without the supervision of a trainer, mainly on account of the high cost of calling a trainer to supervise an exercise session performed in the user's home.
Thus, the only supervision available to a user in most of such cases is the user's own personal discretion and experience, with the aid, for example, of a mirror placed near the exercise tool with which to visually monitor his or her own movements.
Even the benefits of a mirror, however, are limited because the user does not always possess the competence to spot the mistakes he or she is making in doing an exercise and is therefore unable to correct them. Also, the user may not even remember the proper way of performing an exercise, especially when a long time has passed since it was explained by the expert (that is, the trainer). The user thus tends to adopt the wrong postures and to continue to do the exercise without even realizing the mistakes.
Thus, users of fitness equipment (both inside and outside gyms) have long felt the need to be able to do a workout correctly, optimizing the benefits of training and reducing the risks deriving from incorrect postures adopted during the performance of an exercise.
In light of this, several technical solutions are known for monitoring the way a movement is performed for fitness or orthopedic purposes.
For example, patent document EP0336030 describes a system for monitoring load lifting movement, comprising electromyographic sensors connected to the user's muscles and a sensor secured to the user's back in order to measure the angle of the user's back relative to the vertical.
The system also comprises a microprocessor connected to the sensors, a loudspeaker and a bar graph display unit connected to the microprocessor.
The bar graph display provides the user with feedback regarding the amount of force exerted by the muscles on which the sensors are positioned and the microprocessor activates the loudspeaker when the muscle force exerted exceeds predetermined thresholds.
The monitoring system described above is based on measuring predetermined physiological parameters associated with the movement of the user and comparing the measured values of the physiological parameters with preset thresholds.
This monitoring system, however, if used during the performance of a fitness exercise, would not be able to provide indications as to how to perform the exercise correctly, that is to say, corrective instructions that a trainer would provide. In effect, the system can only alert the user when the muscle force exerted exceeds predetermined levels or intensity.
Patent document U.S. Pat. No. 4,830,021 describes a monitoring system for locomotor activity, such as running and/or walking, comprising accelerometers, posture sensors and sensors for measuring the electrical activities of the heart, all secured to the user's body.
The monitoring system also comprises a unit which can record these signals and which can be secured to the user's body.
At the end of an exercise, the user can analyze the data on a computer.
This monitoring system does not therefore provide indications during the workout and, in light of this, at the end of the exercise, the user is not in a position to see whether or not the workout has been performed correctly.
Patent document EP0959956 in the name of Siemens relates to an orthopedic patient monitoring system comprising movement sensors associated with a part of the body and designed to measure pressure and shear forces and acceleration, a first memory for storing the information derived from the sensors, a second memory for a predetermined information model, a comparator for comparing the contents of the two memories and a device for displaying the result of the comparison.
The comparator is configured to compare the contents of the two memories only at the end of the exercise activity when all the information from the sensors is present in the first memory.
In light of this, that monitoring system is unsuitable for providing the type of indications on how to perform an exercise correctly that a trainer would provide.
In addition to the above, another drawback of the monitoring systems described above is that users are loath to wear sensors or monitoring devices.
Patent document U.S. Pat. No. 7,018,211 discloses a procedure for monitoring the performance of a free body exercise and which involves filming the user with a video camera.
That document, however, does not regard exercise machines for muscle power training.
Patent document US2009/131225A1 describes machinery for the rehabilitation of the arms and legs of users with motor disabilities or impairments.
That document, too, therefore, does not regard exercise machines for muscle power training. More specifically, the rehabilitation exercises performed with the machinery described in that document constrain the user's movements to specific postures and thus considerably limit freedom of movement.
Patent document U.S. Pat. No. 6,148,280 describes a system of sensors to be worn to assist a user in performing a movement with a golf club.
Thus, that document, too, does not regard exercise machines for muscle power training. Moreover, the sensors to be worn are uncomfortable for users.
Document WO2009/013679 describes dumb-bells or barbells used for performing fitness exercises and equipped with sensors to keep track of the movement performed by the user moving the dumb-bell or barbell so that, at the end of an exercise, the movement can be compared with a reference graph.
The solution described in that document does not, however, provide effective real-time assistance for a user performing an exercise with a muscle power exercise machine.